My accordion's state of tune

[wirralaccordion]

Being of a somewhat scientific bent I decided to check my accordion’s state of tune, if only on 2 separate reeds ( obviously without taking them out of the box ). The readings on a VITAL tuner were as shown on the attached photo.
I don’t think that anything can be deduced but there are far more knowledgeable members here than myself and so if any one can draw any conclusions from these limited readings I would be most interested to hear them.
All I can think of is that the accordion readings would all have been zero at the time of leaving the factory ( unknown ) and that these readings represent how far the tuning as moved since that time.

 

[debra]

Well, I guess you can hear that some notes are out of tune by playing the L and M register together, as some deviations are big enough to cause a tremolo effect. Also, playing just L or M and then octaves you should also hear tremolo.
But the assumption that all readings would be zero at the time of leaving the factory is wildly optimistic. Accordion tuning in the factory is nowadays a rush job on all but the most expensive instruments. When a note is now 5 cents off I consider it unlikely that it would have been 0 when the accordion was new.

 

[wirralaccordion]

So what tolerance would you expect from a brand new accordion straight out off the factory, say + or - 2 cents?

 

[debra]

So what tolerance would you expect from a brand new accordion straight out off the factory, say + or - 2 cents?

The tolerance expressed in cents depends on the frequency. Basically you do not want to hear any tremolo. Depending on how critical you are you can hear a difference of 1Hz (not very critical ear) or 0.5 Hz (pretty critical ear). At the A=440 a deviation of 1Hz is about 4 cents, 0.5Hz is 2 cents.
So I would say 2 cents is acceptable for the A=440Hz, but one octave higher only 1 cent is acceptable and another octave higher only 0.5 cent is acceptable.